Combined base, water tank, charging unit, and pump housing for oral hygiene instruments



FIG. 1 is a front, right side, top perspective view showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a right side elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof. 

The ornamental design for a combined base, water tank, charging unit, and pump housing for oral hygiene instruments, as shown. 